ESSENTIALS OF DIAGNOSIS
Vasculitides affecting the kidneys are typically associated with hematuria and proteinuria, frequently presenting as a rapidly progressive glomerulonephritis.
Glomerular injury occurs in the setting of the small vessel vasculitides, associated with antineutrophil cytoplasmic autoantibodies (ANCA), antiglomerular basement membrane antibodies (anti-GBM), or the presence of immune complex formation such as with Henoch–Schönlein purpura (HSP), cryoglobulinemic vasculitis, and systemic lupus erythematosus (SLE).
They may affect the kidneys alone, but are more frequently part of a multiorgan disease that may affect the skin, upper and lower respiratory tracts, and the musculoskeletal, gastrointestinal, and nervous systems.
Vasculitides are inflammatory diseases of the blood vessels, which are typically classified by their size (Figure 32–1 and Table 32–1). The following sections will provide an overview of the various kinds of vasculitides. The remainder of this chapter will focus on small vessel vasculitis (SVV) because of its association with glomerulonephritis. The International Chapel Hill Consensus Conference (CHCC) has developed one of the most widely used nomenclature systems which specifies the names and definitions for most forms of vasculitis.
Table 32–1.Names and definitions of vasculitis adopted by the Chapel Hill Consensus Conference on the nomenclature of systemic vasculitis. ||Download (.pdf) Table 32–1. Names and definitions of vasculitis adopted by the Chapel Hill Consensus Conference on the nomenclature of systemic vasculitis.
|Large vessel vasculitis1 |
|Giant cell arteritis ||Granulomatous arteritis of the aorta and its major branches, with a predilection for the extracranial branches of the carotid artery. Often involves the temporal artery. Usually occurs in patients older than 50 years and often is associated with polymyalgia rheumatica. |
|Takayasu arteritis ||Granulomatous inflammation of the aorta and its major branches. Usually occurs in patients younger than 50 years. |
|Medium-sized vessel vasculitis1 |
|Polyarteritis nodosa ||Necrotizing inflammation of medium-sized or small arteries without glomerulonephritis or vasculitis in arterioles, capillaries, or venules. |
|Kawasaki disease ||Arteritis involving large, medium-sized, and small arteries, and associated with mucocutaneous lymph node syndrome. Coronary arteries are often involved. Aorta and veins may be involved. Usually occurs in children. |
|Small vessel vasculitis1 |
|Granulomatosis with polyangiitis2 ||Granulomatous inflammation involving the respiratory tract, and necrotizing vasculitis affecting small to medium-sized vessels, eg, capillaries, venules, arterioles, and arteries. Necrotizing glomerulonephritis is common. |
|Eosinophilic granulomatosis with polyangiitis2 ||Eosinophil-rich and granulomatous inflammation involving the respiratory tract and necrotizing vasculitis affecting small to medium-sized vessels, and associated with asthma and blood eosinophilia. |
|Microscopic polyangiitis2 ||Necrotizing vasculitis with few or no immune deposits affecting small vessels, eg, capillaries, venules, or arterioles. Necrotizing arteritis involving small and medium-sized arteries may be present. Necrotizing glomerulonephritis is very common. Pulmonary capillaritis often occurs. |
|Henoch–Schönlein purpura ||Vasculitis with IgA-dominant immune deposits affecting small vessels, eg, capillaries, venules, or arterioles. Typically involves skin, gut, and glomeruli and is associated with arthralgias or arthritis. |